[loceng]

Well, you'd have to change the freemium plan. I suppose at this point because something was promised, an expectation set, that you'll perhaps upset some people with changes. I would look to see who the top users are usage wise (perhaps cost wise on your part) and what features they use. I imagine there'd be numbers that you could group, perhaps even number of actions per month, etc..

If the top users under freemium no longer want to use the service if you start including them in a paid group, then you have a problem and might have to rethink pricing or the business model overall.